NEW YORK (CNN/Money) - A California man who used personal information from ChoicePoint Inc. and other companies to steal thousands of identities has been sentenced to 5-1/2 years in prison, according to the United States Attorney's office.

Adedayo Benson, a 38-year-old Nigerian national, was sentenced Monday after pleading guilty last November to using and conspiring to use fraudulently obtained credit cards, according to the U.S. Attorney's office in Los Angeles, Calif.

Benson was also ordered to pay nearly $155,000 in restitution to several financial institutions.

Benson's sister, Bibiana Benson, was sentenced to 54 months in federal prison after she pleaded guilty in 2002 to unlawful use of identification, according to federal authorities.

The brother-and-sister team operated a nationwide credit-card fraud scheme, authorities said. Posing as a real estate agent, Bibiana Benson fraudulently opened accounts with several public records database firms, including ChoicePoint Services, Advantage Financial and Equifax.

With access to the companies' databases, Bibiana Benson was then able to obtain personal information on thousands of individuals.

Adedayo Benson opened " mail drops" in Beverly Hills and Encino, Calif., where he would redirect mail from victims' credit card companies. Once he obtained victims' credit card numbers from his sister, Benson could make purchases and get cash advances, according to the authorities.

ChoicePoint recently announced that the Securities and Exchange Commission has opened an informal inquiry and the Federal Trade Commission has begun a separate inquiry into the theft of more than 100,000 consumer profiles.